Timing and number of intrauterine inseminations for best pregnancy outcomes

This study examined which intrauterine insemination (IUI) protocol yields the best pregnancy outcomes in women in which ovulation was induced using medications.

The first line of treatment in many infertile couples is the combination of ovulation induction drugs plus IUI. Induced ovulation involves giving medications, such as clomiphene citrate, to stimulate the ovaries to produce more eggs. The release of these eggs is then triggered using an injection of human chorionic gonadotropin (hCG). Approximately 36 hours following the hCG trigger injection, IUI is performed. This involves injecting processed semen from the male partner directly into the uterus to increase the odds of fertilization.

The authors of this study looked for the optimal timing of IUI that will yield the best pregnancy rate. Their analysis included 1146 fertilization cycles (induced ovulation plus IUI protocol) done between 2007 to 2010. Most women in the study (73.2%) received a single IUI during ovulation, at about 36 hours after the hCG injection. Ovulation was confirmed using an ultrasound examination. The other women in which ovulation was not observed at 36 hours after hCG, were assigned to receive either single or double IUI (introducing semen into the uterus twice).

Results showed that the overall pregnancy rate for each cycle was 10.1%. This was higher in women who had confirmed ovulation (11.7%) compared to women without evidence of ovulation at the time of IUI (6.7%). Pregnancy rates were not significantly different between women receiving single versus double IUI. However, pregnancy rates were higher with double IUI in couples with male-related infertility.

IUI administered when ovulation is confirmed yields better pregnancy rates. In cases where there is male-related infertility, double IUI may help improve outcomes.

This article did not conclusively answer which insemination method was better (single or double IUI).

You should discuss the process of ovulation induction/IUI with your doctor to determine the best course of action in your case.